Herbicidal and plant-growth-regulating N-substituted-N-(2,5-dialkylpyrrol-1-yl) haloacetamides

ABSTRACT

Compounds of the formula: ##STR1## wherein R 1  and R 2  are alkyl or halo; R 3  is hydrogen or alkyl; Z is halo; and R 4  is alkoxycarbonyl, alkoxy, phenyl, substituted phenyl, 
     a group of the formula ##STR2## wherein R 5  and R 6  are hydrogen, alkyl, alkenyl or alkynyl; a group of the formula ##STR3## wherein R 7  and R 8  are hydrogen or alkyl; A five or six-membered aromatic heterocyclic ring of the formula ##STR4## wherein at least one of V, W, X or Y is an oxygen, sulfur or nitrogen atom, R 9  is alkyl and n is 0, 1, 2 or 3 have herbicidal and plant-growth-regulating activity.

This application is a division of Ser. No. 60,320, 7-25-79, now U.S.Pat. No. 4,282,028.

BACKGROUND OF THE INVENTION

Many N-substituted-N-phenyl-haloacetamides are known. For example,compounds containing heterocyclic N-substituents are disclosed in U.S.Pat. Nos. 3,907,544, 4,055,410, 4,097,262, 4,104,051,Offenlegungsschrift Nos. 2,702,102, 2,805,525, and in Belgian Pat. No.863,565.

Other N-phenyl-haloacetamides having amido-containing substituents aredisclosed in U.S. Pat. Nos. 3,944,607 and 3,097,544. Examples ofalkoxycarbonyl and alkoxy-containing N-substituents are disclosed inOffenlegungsschrift No. 2,805,525.

In U.S. Pat. No. 4,141,989, commonly assigned herewith, there aredisclosed fungicidal N-butyrolactone-N-dimethylphenyl-chloroacetamides.

SUMMARY OF THE INVENTION

I have invented a novel class ofN-substituted-N-(2,5-dialkylpyrrol-1-yl) haloacetamides which exhibitherbicidal and plant-growth-regulating activity, herbicidal andplant-growth-regulating compositions thereof and methods of their use.Although a large class of N-substituted-N-(dialkylphenyl) haloacetamidesis known, none wherein the dialkylphenyl group has been replaced by adialkylpyrrol group, as according to my invention, is known. Thecompounds of the invention are generally effective in both pre- andpost-emergent applications and are particularly selective inpre-emergent applications against grassy weeds.

DESCRIPTION OF THE INVENTION

The compounds of the invention are represented by the formula (I):##STR5## wherein R¹ and R² are alkyl of 1 to 3 carbon atoms or halo; R³is hydrogen or alkyl of 1 to 3 carbon atoms; Z is halo; and R⁴ isalkoxycarbonyl of 2 to 6 carbon atoms alkoxy of 1 to 4 carbon atoms;phenyl optionally substituted with 1 to 4 of the same or differentsubstituents selected from halo, alkyl of 1 to 4 carbon atoms or alkoxyof 1 to 4 carbon atoms;

a group of the formula ##STR6## wherein R⁵ and R⁶ are individuallyhydrogen, alkyl of 1 to 4 carbon atoms, alkenyl of 2 to 4 carbon atoms,or alkynyl of 2 to 4 carbon atoms;

a group of the formula ##STR7## wherein R⁷ and R⁸ are individuallyhydrogen of alkyl of 1 to 4 carbon atoms;

a five or six-membered aromatic heterocyclic ring of the formula##STR8## wherein at least one of V, W, X and Y is an O, S or N atom andV, W, X and Y are individually C, O, N or S; R⁹ is alkyl of 1 to 4carbon atoms or phenyl, and n is 0, 1, 2 or 3.

Representative R¹ and R² groups are chloro, bromo, fluoro, methyl,ethyl, i-propyl, n-propyl. Preferably R¹ and R² are methyl.

Representative Z groups are chloro, fluoro, bromo, iodo. Preferably Z ischloro.

Representative R³ alkyl groups are methyl, ethyl, n-propyl, i-propyl.Preferably R³ is hydrogen or methyl.

Representative R⁴ groups are methoxycarbonyl, ethoxycarbonyl, methoxy,ethoxy, propoxy, N,N-dimethylcarbamido, N-methyl-N-ethyl-carbamido,N-methyl-N-allyl-carbamido and N-methyl-N-propargyl-carbamido, phenyl,p-chlorophenyl, p-methoxyphenyl,2,6-di-methylphenyl.

When R⁴ is an oxime, representative R⁷ and R⁸ groups are hydrogen,methyl, ethyl, n-propyl, i-propyl. Preferably R⁷ and R⁸ are methyl.

Preferably R⁴ is a five-membered aromatic heterocyclic ring containingfrom 1 to 3 hetero atoms. Representative rings are 1,2,4-oxadiazol-5-yl,3-methyl-1,2,4-oxadiazol-5-yl, furan-2-yl, 3-methyl-1,2-oxazol-5-yl,1,2-oxazol-3-yl, 2-methyl-1,3-thiazol-5-yl, 1,2-thiazol-3-yl,4-methyl-1,3-thiazol-5-yl. Preferably the ring contains two heteroatoms. Most preferably R⁴ is a thiazole ring optionally substituted withan alkyl group of 1 to 4 carbon atoms preferably a methyl group.

The compounds of the invention may generally be made as follows:##STR9##

Reactions (1) and (2) are known reactions (Chem. and Industry, 1965, p.425). Reaction (3) is a conventional acylation and may be accomplishedby reacting substantially equimolar amounts of the amino-pyrrole andhaloacetyl chloride at room temperature in an inert solvent. Anequimolar amount of an organic amine, such a pyridine or atrialkylamine, may be added to scavenge the hydrogen chlorideby-product.

Reaction (4) may be conducted by combining substantially equimolaramounts of the N-haloacetyl pyrrole (IV), compound (V) and sodiumhydride in an inert solvent at from about -15° C. to about 30° C. If thedesired product (I) is to be an oxime, then the reactant (V) may containthe corresponding carbonyl moiety in the R⁴ substituent. The product ofreaction (4) may then be reacted with hydroxylamine or alkoxylamine toproduce the desired oxime.

The compounds of the present invention are, in general, herbicidal inboth pre- and post-emergent applications. For pre-emergent control ofundesirable vegetation, the herbicidal compounds will be applied inherbicidally effective amounts to the locus or growth medium of thevegetation, e.g., soil infested with seeds and/or seedlings of suchvegetation. Such application will inhibit the growth of or kill theseeds, germinating seeds and seedlings. For post-emergent applications,the herbicidal compounds will be applied directly to the foliage andother plant parts. Generally, the herbicidal compounds of the inventionare effective against weed grasses as well as broad-leaved weeds. Somemay be selective with respect to the type of application and/or type ofweed. The compounds are particularly effective as pre-emergentherbicides against grassy weeds.

The compounds, when applied to growing plants above the ground in suchan amount that the compounds will not kill beneficial plants, also showefficient plant growth regulating or retarding effects and may beadvantageously employed, for example, to prevent or retard the growth oflateral buds in plants and to promote the thinning out of superfluousfruits in various fruit trees.

The compounds can be applied in any of a variety of compositions. Ingeneral, the compounds can be extended with a carrier material of thekind used and commonly referred to in the art such as inert solids,water and organic liquids.

The compounds will be included in such compositions in sufficient amountso that they can exert an herbicidal or growth-regulating effect.Usually from about 0.5 to 95% by weight of the compounds are included insuch formulations.

Solid compositions can be made with inert powders. The compositions thuscan be homogeneous powders that can be used as such, diluted with inertsolids to form dusts, or suspended in a suitable liquid medium for sprayapplication. The powders usually comprise the active ingredient admixedwith minor amounts of conditioning agent. Natural clays, eitherabsorptive, such as attapulgite, or relatively non-absorptive, such aschina clays, diatomaceous earth, synthetic fine silica, calcium silicateand other inert solid carriers of the kind conventionally employed inpowdered herbicidal compositions can be used. The active ingredientusually makes up from 0.5-90% of these powder compositions. The solidsordinarily should be very finely divided. For conversion of the powdersto dusts, talc, pyrophyllite, and the like, are customarily used.

Liquid compositions including the active compounds described above canbe prepared by admixing the compound with a suitable liquid diluentmedium. Typical of the liquid media commonly employed are methanol,benzene, toluene, and the like. The active ingredient usually makes upfrom about 0.5 to 50% of these liquid compositions. Some of thesecompositions are designated to be used as such, and others to beextended with large quantities of water.

Compositions in the form of wettable powders or liquids can also includeone or more surface-active agents, such as wetting, dispersing oremulsifying agents. The surface-active agents cause the compositions ofwettable powders or liquids to disperse or emulsify easily in water togive aqueous sprays.

The surface-active agents employed can be of the anionic, cationic ornonionic type. They include, for example, sodium long-chaincarboxylates, alkyl aryl sulfonates, sodium lauryl sulfate, polyethyleneoxides, lignin sulfonates and other surface-active agents.

When used as a pre-emergent treatment, it is desirable to include afertilizer, an insecticide, a fungicide or another herbicide.

The amount of compound or composition administered will vary with theparticular plant part or plant growth medium which is to be contacted,the general location of application--i.e., sheltered areas such asgreenhouse, as compared to exposed areas such as fields--as well as thedesired type of control. Generally for both pre- and post-emergentherbicidal control, the compounds of the invention are applied at ratesof 0.2 to 60 kg/ha, and the preferred rate is in the range 0.5 to 40kg/ha. For plant growth regulating or retarding activity, it isessential to apply the compounds at a concentration not so high as tokill the plants. Therefore, the application rates for plant growthregulating or retarding activity will generally be lower than the ratesused for killing the plants. Generally, such rates vary from 0.1 to 5kg/ha, and preferably from 0.1 to 3 kg/ha.

Herbicidal and plant-growth-regulating tests on representative compoundsof the invention were made using the following methods.

Pre-Emergent Herbicidal Test

An acetone solution of the test compound was prepared by mixing 375 mgof the compound, 118 mg of a nonionic surfactant and 18 ml of acetone.10 ml of this solution was added to 40 ml of water to give the testsolution.

Seeds of the test vegetation were planted in a pot of soil and the testsolution was sprayed uniformly onto the soil surface at a dose of 27.5micrograms/cm². The pot was watered and placed in a greenhouse. The potwas watered intermittently and observed for seedling emergence, healthof emerging seedlings, etc., for a 3-week period. At the end of thisperiod, the herbicidal effectiveness of the compound was rated based onthe physiological observations. A 0-to-100 scale was used, 0representing no phytotoxicity, 100 representing complete kill. Theresults of these tests appear in Table A.

Post-Emergent Herbicidal Test

The test compound was formulated in the same manner as described abovefor the pre-emergent test. This formulation was uniformly sprayed on 2similar pots of 24-day-old plants (approximately 15 to 25 plants perpot) at a dose of 27.5 microgram/cm². After the plants had dried, theywere placed in a greenhouse and then watered intermittently at theirbases, as needed. The plants were observed periodically for phytotoxiceffects and physiological and morphological responses to the treatment.After 3 weeks, the herbicidal effectiveness of the compound was ratedbased on these observations. A 0-to-100 scale was used, 0 representingno phytotoxicity and 100 representing complete kill. The results ofthese tests appear in Table A.

Root Inhibition of Watergrass Seedlings

Ten watergrass seeds were placed in each of several Northrup-KingSeed-Pack growth pouches. To each pouch was added 15 ml of a 40 ppmaqueous solution of the test compound. The pouches were suspended incontainers under 125-150 foot-candles of light for six days at roomtemperature. Root length is measured for each species and expressed aspercent inhibition compound to check samples treated with the standardMH-30.

Compounds 8, 9, 10, 11 and 12 exhibited root inhibition of 47%, 47%,30%, 38% and 52%, respectively.

For comparison to compounds of the invention, the compounds in Table IIwere prepared. Compound A is the product of Example 2. It can be seen inTable A that Compound A has no measurable herbicidal activity. CompoundB is similar to3-(N-chloroacetyl-N-2,6-dimethylphenylamino)-gamma-butyrolactone (U.S.Pat. No. 4,141,989) except that a 2,5-dimethyl-pyrrol-1-yl group hasbeen substituted in place of the 2,6-dimethylphenyl group. Compound Bhas virtually no herbicidal activity, whereas the compounds areunexpectedly herbicidally active as shown in Table A.

Example 1--Preparation of 2,5-dimethyl-1-amino pyrrole

A mixture of N-amino-phthalimide (50 g) and 2,5-hexadione (35.2 g) in400 ml acetic acid was refluxed for 48 hours, stripped of solvent,slurried in methylene chloride and filtered. The filtrate was washedwith saturated sodium bicarbonate solution, dried and stripped to yieldN-(2,5-dimethylpyrrol-1-yl)-phthalimide (98%).

The phthalimide (57.3 g) and hydrazine (8 gm) were refluxed for 4 hoursin ethanol and filtered. The filtrate was stripped, redissolved inether/methylene chloride, filtered and stripped again to yield the titleproduct.

Example 2--Preparation of N-(2,5-dimethyl-pyrrol-1-yl) chloroacetamide

The product of Example 1 (13.2 g) and pyridine (9.48 g) were stripped inethyl acetate (200 ml) at room temperature with dropwise addition of13.56 g chloroacetyl chloride. The mixture was stirred overnight,stripped, dissolved in methylene chloride, washed with water, dried andstripped. The residue was chromatographed in a silica gel (325 g) column(chloroform elution), to yield the title product (12.27 g).

Example 3--Preparation ofN-(N-methyl-N-propargyl-carbamidomethyl)-N-(2,5-dimethylpyrrol-1-yl)chloroacetamide

To the product of Example 2 (3.91 g) in 200 ml DMF was added sodiumhydride (1.1 g). After stirring for one hour at 0° C.,N-methyl-N-propargyl-bromoacetamide (4 g) was added dropwise. Afterstirring overnight at room temperature the solution was stripped. Theresidue was slurried with 150 ml hexane, and chromatographed on silicagel (30 g ) with methylene chloride elution. Yield 2.4 g of the titleproduct.

Example 4--Preparatation of ethyl2-(N-(2,5-dimethyl-pyrrol-yl)-N-chloroacetyl-amino)propionate

The product of Example 2 (3.17 g), ethyl 2-bromo-propionate (3.08 g) andsodium hydride (0.86 g) in 200 ml DMF were treated at -15° C. accordingto the procedure of Example 3. Work-up yielded 1.7 g of the titleproduct (chromatographed on 120 g silica gel column).

Example 5--Preparation of N-(2-methyl-1,3-thiazol-4-yl)methyl-N-(2,5-dimethylpyrrol-1-yl)cloroacetamide

The product of Example 2 (5.04 g), 2-methyl-4-chloromethyl-1,3-thiazole(4 g) and sodium hydride (1.56 g) in 120 ml dry DMF were treated at 0°C. according to the procedure of Example 3. Work-up yielded 1.67 g oftitle product (chromatographed on silica gel and by h.p.l.c.).

Example 6-Preparation of3-(N-(2,5-dimethylpyrrol-1-yl)-N-chloroacetyl)amino-butan-2-oneO-methyloxime

The product of Example 2 (6.37 g), 3-bromo-butan-2-one (5.13 g) andsodium hydride (1.52 g) in 150 ml dry DMF were treated according to theprocedure of Example 3 to yield 1.5 g3-(N-(2,5dimethylpyrrol-1yl)-N-chloroacetyl)amino-butan-2one.

The butanone (5 g), methoxylamine hydrochloride (1.8 g) and potassiumcarbonate (2.9 g) were stirred in 200 methanol at room temperature,stripped, dissolved in methylene chloride, washed, dried and stripped.The residue was purified by h.p.l.c. to yield 1.87 g of title product.

The other compounds of Table I were prepared in the same manner as theabove Examples.

                                      TABLE I                                     __________________________________________________________________________    COMPOUNDS OF THE FORMULA                                                       ##STR10##                                                                                                 Analysis                                                                mp    C       H     N                                  No.                                                                              R.sup.1                                                                          R.sup.2                                                                          R.sup.3                                                                          R.sup.4    °C.                                                                          Cal Fd  Cal                                                                              Fd Cal                                                                              Fd                              __________________________________________________________________________    1  CH.sub.3                                                                         CH.sub.3                                                                         CH.sub.3                                                                         CO.sub.2 CH.sub.2 CH.sub.3                                                               oil   12.39.sup.a                                                                       11.9.sup.a                                   2  CH.sub.3                                                                         CH.sub.3                                                                         H  CO.sub.2 CH.sub.2 CH.sub.3                                                               41-43 13.03.sup.a                                                                       14.6.sup.a                                   3  CH.sub.3                                                                         CH.sub.3                                                                         H  CON(CH.sub.3).sub.2                                                                      95    13.08.sup.a                                                                       12.8.sup.a                                   4  CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR11## 72-74 56.47                                                                             56.82                                                                             6.72                                                                             5.93                                                                             14.12                                                                            14.18                           5  CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR12## oil   56.85                                                                             56.45                                                                             6.09                                                                             5.99                                                                             14.21                                                                            14.33                           6  CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR13## 44-47 50.97                                                                             48.85                                                                             5.31                                                                             5.29                                                                             19.82                                                                            1970                            7  CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR14## 62-63 58.54                                                                             57.55                                                                             5.63                                                                             5.62                                                                             10.51                                                                            10.19                           8  CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR15## --    55.41                                                                             58.61                                                                             5.68                                                                             6.18                                                                             14.92                                                                            16.55                           9  CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR16## 81-83 53.83                                                                             53.01                                                                             5.23                                                                             5.23                                                                             15.70                                                                            15.67                           10 CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR17## 69-71 52.44                                                                             53.48                                                                             5.38                                                                             5.75                                                                             14.12                                                                            14.53                           11 CH.sub.3                                                                         CH.sub.3                                                                         H                                                                                 ##STR18## 88-89 50.79                                                                             51.13                                                                             4.97                                                                             5.16                                                                             14.8                                                                             14.66                           12 C.sub. 2 H.sub.5                                                                 C.sub.2 H.sub.5                                                                  H  OCH.sub.3  33-38 55.71                                                                             49.46                                                                             7.35                                                                             6.56                                                                             10.83                                                                            10.06                           13 CH.sub.3                                                                         CH.sub.3                                                                         H  OCH.sub.3  120-127                                                                             52.06                                                                             52.18                                                                             6.51                                                                             6.50                                                                             12.15                                                                            12.46                           14 CH.sub.3                                                                         CH.sub.3                                                                         CH.sub.3                                                                          ##STR19## oil   54.64                                                                             57.42                                                                             7.01                                                                             7.03                                                                             14.71                                                                            15.17                           __________________________________________________________________________     .sup.a Chlorine                                                          

                  TABLE II                                                        ______________________________________                                        COMPOUNDS OF THE FORMULA                                                       ##STR20##                                                                                           Analysis                                                             mp       Cl                                                     No.      R          °C. Cal  Fd                                        ______________________________________                                        A        H           86-88     19.04                                                                              20.8                                                ##STR21## 130-131    13.12                                                                              12.2                                      ______________________________________                                    

                  TABLE A                                                         ______________________________________                                        HERBICIDAL ACTIVITY                                                           % Control Pre/Post                                                            No.    L       M       P      C     W     O                                   ______________________________________                                        A      0/0     0/0     0/0    0/0   0/0   0/0                                 B      0/0     0/0     35/0   0/0   0/0   0/0                                 1      20/0    10/0    25/0   93/0  100/0 95/0                                2      0/0     0/0     0/0    85/0  98/75 90/35                               3      40/0    20/0    50/0   92/20 98/30 95/20                               4      0/0     10/0    0/0    70/0  99/0  90/0                                5      0/0     0/0     35/0   90/0  100/55                                                                              85/40                               6      0/0     15/0    25/0   70/0  100/0 93/0                                7      70/0    55/0    70/0   95/0  100/60                                                                              100/60                              8      0/0     0/0     60/0   90/0  100/30                                                                              60/0                                9      90/35   35/10   98/30  95/75 100/75                                                                              93/35                               10     20/0    20/0    20/0   100/65                                                                              100/65                                                                              95/55                               11     0/0     0/0     50/0   100/70                                                                              100/75                                                                              95/40                               12     100/0   60/0    40/0   100/0 100/0 83/0                                13     94/0    80/10   35/0   97/0  100/25                                                                              93/0                                14     100/0   60/0    30/0   90/20 100/75                                                                              --/55                               ______________________________________                                         L = Lambsquarter (Chenopodium album)                                          M = Mustard (Brassica arvensis)                                               P = Pigweed (Amaranthus retroflexus)                                          C = Crabgrass (Digitaria sanguinalis)                                         W = Watergrass (Echinochloa                                                   O = Wild Oats (Avena fatua)                                              

What is claimed is:
 1. A compound having the formula: ##STR22## whereinR¹ and R² are alkyl of 1 to 3 carbon atoms or halo; R³ is hydrogen oralkyl of 1 to 3 carbon atoms; z is halo and R⁴ is isothiazolyloptionally substituted at a ring carbon with an alkyl group having 1 to4 carbon atoms or phenyl.
 2. A compound according to claim 1 wherein R¹and R² are methyl, z is chloro, and R³ is hydrogen.
 3. A compoundaccording to claim 2 wherein R⁴ is 1,2-thiazol-3yl.
 4. A grassherbicidal composition comprising a biologically inert carrier and anherbicidally effective amount of the compound of the formula defined inclaim
 1. 5. A method for controlling grasses which comprises applying tosaid vegetation or its growth environment an herbicidally effectiveamount of the compound of the formula defined in claim 1.